Membrane roofing

ABSTRACT

A foam roofing underlayment is provided with a reinforcement membrane having an array of fastener elements for engaging fastener elements on a flexible roof membrane. The underlayment is formed by molding foam between the reinforcement membrane and a carrier membrane. The underlayment in secured to the roof using washers having fastener elements for engaging the fastener elements of the flexible roof membrane. An anti-peel flap with fastener elements is provided around the periphery of the washers. A slip sheet is used between the underlayment and the flexible roof membrane to permit accurate positioning of the flexible roof membrane prior to engagement of the fastener elements. The interstices between the fastener elements provide lateral moisture paths to vents in the flexible roof membrane.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to provisional U.S. Application Ser.No. 61/043,983, filed on Apr. 10, 2008, the entire contents of which areincorporated herein by reference in their entirety.

TECHNICAL FIELD

This invention relates to securing exterior building constructionmaterials, such as roof membranes and siding that are exposed toenvironmental forces such as wind and rain.

BACKGROUND

Some buildings have roofs that are shingled. Some others have membraneroofs, in which a flexible membrane forms the outer environmentalbarrier. Many membrane roofs are flat or slightly sloped or arched. Ingeneral, roofing membranes are secured over rigid insulation boards,such as foam boards, that increase the thermal barrier properties of theroof.

Membrane roofs, like other roofs, must withstand severe environmentalconditions, including high winds and hail. Winds can cause largepressure differentials across the roof membrane, and can actually liftor separate the membrane from the roof.

Wind uplift occurs when the air pressure below the roof system isgreater than that above the system as wind flows over the buildingdecreasing the pressure directly above the roof surface. The atmosphericpressure below the roof attempts to equalize this pressure differential,causing an upward push of air referred to as wind uplift.

The Underwriters Laboratories has developed a standard uplift test, theUL580 uplift test, to test the ability of membrane roofing constructionsto withstand the high uplift forces that can be caused by high winds.

FM Global Approval LLC also provides uplift pressure and uplift pulltest standards to ensure that “Mechanically attached assemblies tested .. . shall resist a minimum uplift pressure of 60 psf (2.9 KPa) whentested by the FM Approvals Uplift Pressure Test procedures . . . withoutrelease from the deck, and shall be maintained in place.” The current,relevant UL and FM Global Approval Standard uplift test standards areincorporated herein by reference. Other industry standards also providefor testing roofing installations against conditions corresponding tohail, standing water, foot traffic, fire, and corrosion.

The FM Global Approval Standard #4470 defines “wind uplift” as:

The force generated by wind on a roof system or components in a roofsystem resulting from wind-induced pressures. Wind that is deflectedaround and across the surfaces of a building causes a drop in airpressure immediately above the roof surface (negative pressure); the airin the building will flow beneath the roof deck (positive pressure), andthe combined uplift pressures tend to lift the roof upward. Wind upliftmay also be caused by the introduction of wind underneath the roof edgeswhere it can cause the roof assembly to pull away from the substrate.Roof loss by wind can be avoided, or prevented, by proper installationand adequate adhesion, attachment, or ballasting.

New roofing constructions and methods are sought to providecost-effective installation and satisfactory uplift load resistance.Similarly, new constructions and methods are sought to retain otherexterior construction materials, such as shingles and siding, tobuildings or other structures.

SUMMARY

The details of one or more embodiments of the invention are set forth inthe accompanying drawings and the description below. Other features,objects, and advantages of the invention will be apparent from thedescription and drawings, and from the claims.

One aspect of the invention features a construction underlaymentincluding a rigid foam board having two broadest sides defining athickness therebetween; and a reinforcing facing including a flexiblebase bonded across one of the broadest board sides and an array of touchfastener elements extending from the base and exposed for engagement.

In one implementation, the facing base is bonded directly to foam of theboard. The facing can extend across an entire lateral extent of theboard to cover substantially all of one of the broadest board sides. Thearray of touch fastener elements can cover substantially all of one ofthe broadest board sides.

In one example, the facing base includes a flexible resin membrane andthe touch fastener elements have individual resin stems extendingintegrally from a surface of the membrane. In some cases, the touchfastener elements have molded heads defining overhangs for engagingfibrous loops.

In another implementation, the facing base further includes a tie layerbetween the membrane and the foam board. The tie layer can include areinforcing scrim. The scrim can include fibers at least partiallyembedded in resin of the membrane and formed of a material selected toenhance bonding between the scrim fibers and the membrane resin. The tielayer of the reinforcing membrane can be made of glass fiber to improvedimensional stability and fire resistance.

In other implementations, float yarns are provided to further strengthenthe closure and transfer the load between the fastener elements and loopfilaments. Use of such float yarn in a touch fastener closure isdescribed in U.S. Pub. No. 2005-0081342, titled Plastic SheetReinforcement, which is incorporated herein in its entirety byreference.

Still in other implementations, a scrim or tie layer is not necessary,for example, where fastener elements are bonded directly to a substrate.Bonding may be accomplished using adhesives or any known mechanical orchemical bonding mechanism.

In some cases, the foam board defines foam knit lines extending along alength of the board between adjacent foam portions, and the tie layerincludes fibers disposed across the knit lines. In some cases theconstruction underlayment further includes a second resin membraneextending across an opposite broad side of the board. The resin membranecan be in an annealed state.

In one implementation, the construction underlayment further includes atouch 1 fastener material on a side of the foam board opposite thereinforcing facing.

In another implementation, the touch fastener elements compriseindividual exposed fiber loops or fiber segments of a field ofhook-engageable fibrous material.

The broad sides of the foam boards, for some installations, each have alength and width and define a surface area of about 3 square meters (32square feet). In some cases, the length of the foam board is at leastabout 1.2 meters (4 feet). In some cases, the facing base is continuousover at least about 24 inches (61 cm) in each of two orthogonaldimensions. Other common dimensions for construction materials include,2 ft×4 ft (61 cm×122 cm), 4 ft×4 ft (122 cm×122 cm), and 2 ft×8 ft (61cm×244 cm). The thickness of the foam board can range from about 0.25inch (6.3 mm) to 4 inches (10 cm) and can be tapered to improvedrainage.

In one implementation, the array of touch fastener elements has adensity of about 1700 hooks per square inch (265 per square cm) and thetouch fastener elements extend about 0.015 inch (0.4 mm) from the faceof the membrane and are about 0.005 to 0.006 inch (0.13 to 0.15 mm)thick.

In some cases, the board has a nominal thickness of between 0.635 and10.16 cm (0.25-4.0 in,) and a flexural strength of between at leastabout 275 to 689 KPa (40-100 psi), as tested in accordance with ASTM C473, to support installation and precipitation loads across the span ofthe flutes of the roof decking.

In some cases, the facing base has a thickness, not including thefastener elements, of between about three and ten thousandths of aninch.

In some implementations, the facing base includes a tie layer betweenthe membrane and the foam board. In some cases, the tie layer is paper,tissue paper or a non-woven fabric. The fabric includes a coatingchemically bonded to the foam.

In some implementations, the reinforcing membrane is formed ofpolypropylene, nylon, polyester PVC, polyethylene, ethylene propylene orother suitable resins.

In some implementations, reinforcing membranes comprising touch fastenermaterial covers the two broadest sides of the foam board. In some cases,application of similar touch fastener materials on the two broadestsides contributes to the dimensional stability, and particularly, theplanarity or flatness of the foam board.

In some implementations, application of touch fastener material to bothbroadest sides allows the foam boards to be attached to one another in alayered configuration. In some cases, the adjacent touch fastenermaterials on two opposing layered foam boards are engageable. In othercases, a separate interfacing touch fastener material is interposedbetween the layered foam boards. For example, a material with loopspresent on both broad faces can be used between two foam boards facedwith hook fastener material in a layered arrangement.

In some implementations, multiple foam boards are stacked to achieveincreased R-values. In some cases, a first foam board layer is attachedto the roof deck using fasteners and a second foam board layer isattached to the first layer using touch fasteners. Alternatively, thesecond foam board layer can be adhered to the first foam board.

In some instances, board layers can be stacked using an intermediateloop layer or by using alternating hook faced and loop faced boards. Forexample, an alternating stacked arrangement of hook faced boards withloop faced boards can be used for stacked roofing installations. Inother instances, stacked board layers can be adhered together.

Such layered arrangements avoid thermal bridging caused by conduction ofheat through full-length metal fasteners that typically extend betweenthe roof decking and roof membrane in conventional installations.Thermal bridging is often evidenced in conventional installations bymelted circles above full-length fasteners in light snow cover.

Thus, a stacked arrangement provides improved R values throughadditional layers and through elimination of thermal bridging acrossmetal through fasteners.

In various implementations, different combination of hook and loop touchfastener material, loop and hook touch fastener material, self-engaginghook touch fastener materials can be used to form suitable facings andtouch fastenings between mating surfaces.

For example, in some cases, the broad sides of the foam board arecovered with loop touch fastener material. The loop material can be anonwoven, spun bond or Velcro brand FNL series loop material. The loopmaterial and the touch fastenings as a whole serves to reinforce thefoam board in the installation.

In some implementations, the hook touch fastener material is present onthe roofing membrane and loop touch fastener material is present on thefoam board.

Another aspect of the invention features a construction insulation boardincluding a rigid foam board having two broadest sides defining athickness therebetween; and a reinforcing facing comprising a flexibletouch fastener material bonded across one of the broadest board sidesexposed for engagement across the board with a cooperative touchfastener material.

In some implementations, the touch fastener elements comprise touchfastener elements configured to engage a cooperative field of loopfibers to form a releasable fastening. In some implementations, thetouch fastener material includes one of an array of male touch fastenerelements and a field of loops.

In some implementations, the board includes a second reinforcing facingof a second touch fastener material bonded across the second broadestface of the foam board.

In another, alternative aspect, the invention features a method offorming construction underlayment. The method includes introducing alongitudinally continuous facing into a molding channel, the facingincludes a flexible sheet-form base and an array of fastener elementsextending from a fastening side of the base directed toward a surface ofthe molding channel. The method further includes introducing liquidresin to the molding channel, the liquid resin containing a foam agentthat causes the liquid resin to foam to expand and fill the moldingchannel on a back side of the facing base, such that the foamed resinbonds to the facing. The method further includes solidifying the foamedresin to form a resin board having the facing bonded thereto.

In some cases, the molding channel is a substantially open corridor ortrench and in other cases it is a substantially closed tube. Thus, thefoam board underlayment can be formed using a free rise process with asingle belted surface or a restrained rise process with upper and lowerbelted or restraining surfaces.

In some free rise applications a polyisocyanate foam is appliedinitially to a single facing layer of touch fastener material on aconveyor belt. In the free-rise process, a measured amount of liquidfoam is applied to a lower facing and is allowed to flow and rise as thesecond facing layer is applied. The resulting foam thickness ispredetermined as a function of the volume of foam applied. The free riseprocess is generally suitable for forming board thickness between about¼″ and 1.5″ (6-38 mm) in thickness.

In other cases, the paper/facer is used during formation of the foamboard and the hook material is post-adhered to the formed foam board.The hook material can be applied in-line or during a post-laminatingstep.

In some applications, the liquid resin is introduced as parallel lanesof resin that expand to form a single contiguous foam structure havingcorresponding knit lines, with the facing spanning multiple knit lines.

In other applications, the method includes introducing a carrier sheetto the molding channel, with the liquid resin disposed between thecarrier sheet and the facing, such that the carrier sheet forms anopposite surface of the resin board.

The liquid foam can be carried into the molding channel on the carriersheet.

In some cases, the carrier sheet includes fastener elements exposed on aface of the carrier sheet directed away from the liquid resin.

In some cases, the molding channel is formed by opposing belts thatconvey the resin and facing along the channel as the resin foams. Thebelts can include interconnected rigid belt segments. Segments of one ofthe belts can have extensions that come together to form side walls ofthe molding channel.

In some applications, the facing base includes a flexible resin membraneand the method includes bonding the foamed resin to the resin membrane.Prior to introducing the facing the facing membrane can be annealed. Insome cases, annealing the membrane includes heating and manipulating themembrane. In some cases, annealing the membrane includes applyingtension sufficient to cause local resin yielding. In other cases,annealing the membrane includes passing the membrane through a series ofdancer rolls.

In some applications, the facing sheet is laminated to a continuousboard material which is then cut into discrete board segments.

In other applications, the facing sheet is laminated to the boardmaterial after molding of the board material. The facing sheet caninclude a paper sheet.

In other applications, the facing material includes a paper backing.

In some applications, a tire resistant roofing board (e.g., gypsumboard, DENSDECK™, or SECUROCK™ brand board) is installed under or overthe foam board. A complementary or cooperating hook or loop touchfastener material can be applied to plywood, expanded polystyrene (EPS),extruded polystyrene (XPS), wood fiber board, perlite board, extrudedplastic sheets, vacuum formed plastic sheets, corrugated sheeting,cementitous wood fiber board (e.g., Tectum™ brand board), DENSDECK™ orSECUROCK™ (gypsum), lightweight concrete board, lightweight insulatingconcrete board or other roofing or construction material.

For example, a fire resistant roofing board can be applied over the foamboard. The fire resistant board can include a reinforcing membrane withan array of male fastener elements for attachment of the roofingmembrane.

In some cases, the roofing membrane includes a weatherable and fireresistant material. In some cases the roofing membrane includes areinforcing fabric of glass or polyester.

In some cases, the foam board, touch fastener material facing and touchfastening are selected to provide increased hail damage resistance. Inconventional installations with the roofing membrane adhered to a paperor foil faced foam board, sever hail impacts cause tearing or creasingof the facing and separation of the roofing membrane from the underlyingfoam board. This can create a separated initiation location for lateruplift separation.

In contrast, the touch fastener facing on the foam board serves toabsorb and distribute hail impact forces, maintaining engagement betweenthe membrane and foam board. For example, plastic deformation of thefoam board and touch fastener material facing can absorb hail impactforces that would typically tear or crease conventional foil and paperfoam board facing materials. The touch fastener closure between the roofmembrane and foam board remains engaged even after such plasticdeformation, preventing the impact points from becoming separationinitiation points later during uplift loading.

In some cases, the roofing deck includes concrete, corrugated steel,exterior plywood or other substantially rigid deck material.

In another aspect, the invention features a roof including a roof deck;underlayment secured to the roof deck, the underlayment including one ormore rigid foam boards each having a reinforcing membrane bonded acrossan upper surface of the board, the reinforcing membrane formed of aflexible resin and carrying an array of fastener elements having stemsformed of the flexible resin; and a flexible roof membrane extendingover the underlayment, the roof membrane including a water-impervioussheet with a field of fastener elements exposed on an underside thereofand engaged with the fastener elements of the underlayment to secure theroof membrane.

In some implementations, the field of fastener elements of the roofmembrane includes a field of hook-engageable loops.

In some cases, the fastener elements of the underlayment and the loopsof the roof membrane form a fastening with a nominal shear slack ofabout 1.524 mm±0.762 mm (0.060 in±0.03 in), i.e., between about 0.762 mm(0.030 inch) and 1.524 mm (0.090 inch) or between about 1.27 mm (0.050inch) and 1.778 mm (0.070 inch).

In some implementations, the roof is constructed to withstand up-liftforces of at least about 4.309 Newton/square meter (90 pound/squarefoot), at least about 7.182 Newton/square meter (150 pound/square foot),or at least about 10.773 Newton/square meter (225 pound/square loot). Insome cases, the materials and configuration of the foam board, touch(listener materials, roofing membrane can be selected to achieve evenhigher uplift resistance, for example, in known hurricane regions.

In some implementations, the roof is constructed to withstand an averageper hook up-lift force of at least about 0.022 Newton per hook (0.005lbf/hook), at least about 0.067 Newton/hook (0.015 lbf/hook) andpreferably at least about 0.133 Newton/hook (0.030 lbf/hook). Where notall hooks are fully engaged in a given fastening, an average force perhook can still be determined through uplift testing as described below.

In some cases, the fastener elements are mushroom shaped.

In some cases, the underlayment is secured to the roof deck by engagedtouch fasteners.

In some implementations, the underlayment is secured to the roof deck inpart by washers having fastener elements for engaging fastener elementson the roof membrane.

In some implementations, the washers do not include touch fastenerelements. For example, the washers can be smooth or ribbed and can bemade of steel or plastic. Suitable membrane roofing washers and screwsare available under the Trufast™ brand. Also, the insulation board canbe attached to one another and/or to the roof deck with hot asphalt orwith adhesive, e.g., Insta-Stik™ brand urethane adhesive.

The washer can include a peripheral anti-peel flap having fastenerelements for engaging fastener elements on the roof membrane.

The water-impervious sheet can include an outer surface exposed toatmosphere.

In some implementations, ballast is secured to an upper surface of themembrane by touch fastener elements. For example, paver block ballastcan be distributed along the roof edges and secured to the membrane bytouch fastener elements.

In some implementations, multiple layers of underlayment and stackedtogether with a lower layer secured to the roof deck via throughfasteners and an upper layer secured via one of touch fastener elementsand adhesive.

In another aspect, the invention features a method of roofing astructure. The method includes securing an underlayment to a roof deck,the underlayment includes one or more rigid foam boards each having aflexible resin reinforcing membrane bonded across an upper surface ofthe board and carrying an array of fastener elements having stems formedof the flexible resin; positioning a flexible roof membrane to extendover the underlayment, the roof membrane includes a water-impervioussheet with a field of fastener elements exposed on an underside thereofto engage with the fastener elements of the underlayment to secure theroof membrane; and mechanically enhancing engagement of the fastenerelements of the flexible roof membrane and underlayment.

Enhancing engagement can include at least one of rolling, orbitalmassaging and multi-directional stretching.

Some applications include providing a slip sheet between theunderlayment and the flexible roof membrane to prevent engagement of therespective fastener elements of the underlayment and roof membrane. Themethod further includes adjusting the positioning of the flexible roofmembrane over the underlayment; and moving the slip sheet to allowengagement of the fastener elements of the flexible roof membrane andunderlayment.

In some applications, the method includes positioning a second slipsheet adjacent the first slip sheet to prevent the fastener elementsfrom engaging beyond the region of the first slip sheet.

Moving the slip sheet can include incrementally advancing the slip sheetbetween the flexible roof membrane and the underlayment to engageincremental sections of the fastener elements of the flexible roofmembrane and the underlayment. Alternatively, moving the slip sheet caninclude removing the slip sheet from between the flexible roof membraneand the underlayment.

In some cases, engagement is indicated by witness marks or other visualaids that indicate either treatment by an engagement enhancing processor engagement itself.

In some cases, positioning the flexible roof membrane includessimultaneously unrolling the flexible roof membrane and the slip sheetpreviously rolled up with the flexible roof membrane.

In some applications, the method includes providing multiple ventsthrough the flexible roof membrane to permit the escape of moisture frombeneath the flexible roof membrane, the interstices between the engagedfastener elements provide lateral moisture paths to the vents.

In some installations, a vented roof includes pressure passages throughthe membrane roofing installation to neutralize upward pressuredifferentials in high winds. One known vented installation is commonlyknown as the Stevens Vented Roof System. Such systems are designed toneutralize the pressure differentials caused by wind and keep themembrane tightly secured to a roofing deck or air barrier over steel orwood.

In some cases, perforated tubes are disposed between the membrane andthe underlayment to provide ambient or forced air flow and/or venting.

Various features of the invention are applicable in totally adhered,partially adhered, and mechanically attached roofing applications. Forexample, in some cases, fastener elements across the broad surface ofthe membrane can engage mating fastener elements on an underlayment,including single or batten-type fasteners.

DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of a partially constructed membrane roof.

FIG. 2 is a cross-section view of the completed membrane roof.

FIG. 3 is an enlarged cross-sectional view of the roof, showing aroofing underlayment fastener.

FIG. 4 is a perspective view of one of the rigid foam underlaymentboards of the roof of FIG. 1.

FIG. 5 is a cross-sectional view of an underlayment board having a hookfastener reinforcing membrane as a facing on one side and a paper facingon the other side.

FIG. 6 is an enlarged cross-sectional view showing a reinforcedboard-membrane interface.

FIG. 7 is a side view of one end of a roofing membrane sheet.

FIG. 8A shows an overlapped roofing membrane joint.

FIG. 8B shows a roofing membrane butt joint with an overlapping jointcover.

FIG. 9A is a perspective view of a partially constructed shingle roof.

FIG. 9B is a side view of one of the shingles of FIG. 9A.

FIG. 10 illustrates an apparatus and method for forming reinforcedconstruction underlayment boards.

FIG. 11 is a perspective view of the portion of the apparatus of FIG. 10preceding the heater entrance, showing the application of foaming resin,but with the moving chain segments removed for clarity.

FIG. 12 is a cross-sectional view taken along line 12-12 in FIG. 10.

FIG. 13 illustrates another foaming resin spray pattern and apparatus.

FIG. 14 illustrates an apparatus and method for annealing a continuousresin membrane.

FIG. 15A is perspective view of a washer having fastener elements.

FIG. 15B is a perspective view of a washer having fastener elements anda peripheral anti-peel flap.

FIG. 15C is a cross-sectional view of a washer having a peripheralanti-peel flap, taken along line 15C-15C in FIG. 15B.

FIG. 16A is a side view of a rigid substrate having anti-peel flaps in afirst no load position.

FIG. 16B is a side view of a rigid substrate having anti-peel flaps in asecond loaded position.

FIG. 16C is a side view of a rigid substrate having a partiallyreleasable anti-peel flap in a loaded position.

FIG. 17 is a side view of a washer having flexible anti-peel portions.

FIG. 18 is a perspective view of installation of a membrane roof.

FIG. 19 is a side view of a membrane roof installation including vents.

FIG. 20 is a side view of a vented roof installation.

FIG. 21 is a side view of a ballasted roofing installation.

FIG. 22 is a side view of an inverted roofing installation.

FIG. 23 is a side view of stacked or layered foam board installation.

FIG. 24 is a perspective view of a test fixture for performing simulateduplift tests.

FIG. 25 is a side view of a shear slack test of a hook and loopcombination.

FIG. 26 is a side view of a single hook and loop fastening during shearslack testing.

FIG. 27 is a plot illustrating shear slack in sample fastenings.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

Referring first to FIGS. 1 and 2, a roof 10, such as of a house orcommercial structure, includes a structural roof deck 12 to which rigidinsulation 14 is secured. A roofing membrane 16 is then secured over therigid insulation as an environmental barrier. The roof deck 12 may befashioned of corrugated metal sheet as shown, or of wood, concrete,cementitious wood fiber (e.g., Tectum™), lightweight concrete andlightweight insulating concrete and/or structural beams, for example,and provides a supporting surface for the roof. The rigid insulation 14is made up of several rigid boards placed edge to edge across the roofdeck to form an underlayment that serves as a thermal barrier. Typicalboard sizes are 4 ft×8 ft (1.2×2.4 meters) or 2 ft×4 ft (0.6×1.2meters), 4 ft×4 ft (1.2×1.2 meters) and 2 ft×8 (0.6×2.4 meters). Thethickness of the foam board can range from about 0.25 in to 4 in(0.635-10.16 cm), in some cases between 1.5 and 2.0 inches (37 to 50mm), for example, and may be stacked for increased thickness orinsulation or tapered for improved drainage. Touch fasteners may also beused to bond stacked layers. Board thickness may also be varied, forexample, to produce a tapered panel for improved watershed, drainage orinsulation capacity. In these examples the rigid boards are formedprimarily of foam, with upper and/or lower skins of materials to bediscussed below. The membrane 16 may be of EPDM, PVC, TPO or otherresin, or modified bitumen membrane, for example, and provides an outerroof surface that resists water intrusion and protects the roof fromenvironmental damage.

The insulation 14 may be secured to the roof deck 12 by threadedsingle-type fasteners 18 and load distribution washers 20, as shown inFIGS. 1 and 3, or by touch fasteners (e.g., hook-and-loop fasteners), asshown in FIG. 2 and discussed further below. Alternatively oradditionally, battens may also be used in combination with themechanical fastening systems described herein. If by threaded fasteners,the fasteners may be of 0.168 inch (4.3 mm) shank diameter and arrangedin any pattern known in the art, and typically include washers 20 ofabout two to three inch (51-75 mm) diameter to distribute the fasteningload through the foam.

Single-type fasteners 18 are installed in a pattern with washers 20installed thereon to provide increased stress distribution. Fasteners 18can be selected to penetrate the roofing structures to a desired depth.Portions of membrane 16 can be reinforced as predetermined locations forfasteners 18, reducing the number or size of fasteners 18 or washers 20.Any type, number, size and pattern of fasteners 18 and washers 20 can be(a) installed under membrane 16 with adhesive applied to the top surfaceof washers 20; (b) installed through membrane 16 and sealed (i.e.,piercing membrane 16); (c) installed within the lap of overlappingportions of membrane 16; or (d) applied under membrane 16 with anintegral fastener above (e.g., non-piercing types). Thus, fasteners 18are but one example of use of distributed single-type fasteners tosecure membrane 16. Suitable washers and threaded fasteners and areavailable from Trufast, LLC of Bryan, Ohio under the product names MP-3Plates and DP Fasteners.

Referring next to FIGS. 4 and 5, board 22 of rigid foam insulation 14 isa rectangular structure having a length, width, and a thicknesssubstantially less than the width or length. Notably, it has areinforcing membrane 24 bonded across a broad surface of the board andformed of a flexible resin. The reinforcing membrane 24 carries an arrayof male fastener elements 26 having stems formed of the flexible resinforming the membrane. Membrane 24 is shown as covering the upper surfaceof board 22 in FIG. 4, which is inverted in FIG. 5. The fastenerelements may be hook-shaped, as shown in FIG. 5, or mushroom-shaped, forexample. Other fastener element shapes may be substituted, depending onthe application. In this example the fastener elements are of a CFM-29shape, available from Velcro USA, Inc. of Manchester, N.H., anddescribed in U.S. Pat. No. 5,900,350, the entire contents of which arehereby incorporated by reference. Other methods of forming fastenerelements are disclosed in U.S. Pat. Nos. 5,505,747, 4,894,060 and5,058,247, each of which are also incorporated herein in their entirety.

Membrane 24, with its hooking elements, forms a flexible reinforcinglayer or skin across the entire board 22. This provides a means ofsecuring the roof membrane to the board, while at the same timeincreasing the ability of the board to withstand uplift loads applied,for example, by extreme winds. It is believed that the improved loadcapacity of the roofing underlayment from the presence of the boardreinforcing membrane may be more than a ‘skin effect’, as the membranespans and reinforces knit lines and other weak regions of the board thatcan be caused by the manufacturing and roof fastening processes. Thecombination of the broad area of coverage of the membrane with themulti-point load transfer, function provided by the touch fastenerinterface between the reinforcing membrane 24 and the underside of theroofing membrane 16 is of particular advantage, due at least in part tothe ability of the touch fastener interface to maintain a significantload resistance while absorbing significant relative displacement at theinterface, such as may be induced by extreme load conditions at discretedeck fasteners. Preferably, reinforcing membrane 24 covers at least 80percent (better still, at least 90 percent) of the area of one face ofthe insulation board. Most preferably, reinforcing membrane 24 coversthe entire (or substantially entire) broad surface of the insulationboard. Membranes that span substantially the full width and length ofthe board as a single, continuous substrate are preferred, as opposed toareas covered by discrete, adjoining strips, although single continuousmembranes covering at least half of both the width and length of theboard are useful. For example, for a 4 by 8 foot (1.2×2.4 m) board, areinforcing membrane of at least 24 inches (60 cm) in width, 48 inches(1.2 m) in length is preferred. Roof deck fasteners and associatedwashers, if employed (see FIG. 3) will cover discrete regions of thetouch fasteners, but care should be taken to maintain the availabilityof the fastener elements over a substantial portion of the surface ofthe board so as to obtain a maximum amount of the securement andreinforcement effects of the membrane.

Referring back to FIG. 3, by means of illustration only, a high windvelocity can create a very low roof surface pressure, approaching anabsolute vacuum. Simultaneously, high pressures can be developed withinthe roof, under the foam insulation boards 14. That relatively highpressure can be transferred to the interface between insulation 14 andmembrane 16 by air flow at the edges of adjacent boards, or along thethreaded fasteners. High pressure loads reaching the insulation-membraneinterface via fastener 18 will, due to the limited air-permeability ofthe touch fastener interface, be controllably distributed away fromwasher 20 to place the entire interface in tension, rather than actingat an edge of an adhesive insulation-membrane interface around fastener18 and progressively failing the adhesive bond. The touch fastenerinterface enables local and small relative displacement of the roofingmembrane 16 with respect to the rigid underlayment, allowing themembrane to move to distribute localized loads that would otherwisecause local failure. Across the insulation, even under washer 20 wherethe fastener elements are inoperable, the presence of membrane 24reinforces the foam substrate. Furthermore, it is believed that loadcycles may even increase the strength of the touch fastener interface,due to minute displacements that occur across the fastener field andenhance engagement between great numbers of hooks and loops. Suchengagement enhancement may also result from thermal expansion cycling.Such effects may actually improve the strength of the roof over time.

In some examples, the hooks of hook membrane 24 are preferablyconfigured with sufficient column strength, hook density and height toresist crushing from foot traffic, installation or other forces.Increased lateral column strength may be provided by shorter, thicker,and more closely arranged hooks believed to be desirable in certain hightraffic or heavy load applications. A short mushroom-style hook isbelieved to be well suited to such applications. An example of amushroom-style hook is the 3M brand SJ3506 hook product.

In one example hook membrane 24 is formed of polypropylene, and has ahook density of about 1700 hooks per square inch (265 per square cm).The hooks themselves extend about 0.015 inch (0.4 mm) from the face ofthe membrane, which is about 0.005 to 0.006 inch (0.13 to 0.15 mm)thick, exclusive of the fastener elements. These relatively shorter,sturdier hooks and high hook densities are considered advantageous inavoiding damage from foot traffic during roof construction, particularlybefore the roof membrane is installed.

To further increase the reinforcement properties of the membrane,membrane 24 is itself reinforced with a very light non-woven fabric.Such fabrics, and methods of making them, are disclosed in pending U.S.application Ser. No. 10/728,138 (published as US2004/0157036A1) and Ser.No. 11/102,455 (published as US2005/0196580A1), the contents of both ofwhich are hereby incorporated by reference. Such reinforcing fabrics canbe directly laminated into the resin of the membrane as the membrane isbeing formed, by the methods taught in U.S. Pat. No. 5,518,795, forexample, the contents of which are also incorporated herein byreference. As shown in FIG. 6, the reinforcing fabric 28 may be embeddedin the back surface of the resin membrane 24 and exposed for securingthe membrane either directly to the foam 14 (as shown in FIG. 6) or toan intermediate tie layer, such as an adhesive. For enhancing thebonding of the reinforcing fabric directly to urethane-based foam, forexample, a urethane binder coat may be employed in the construction ofthe fabric. The membrane may alternatively be formed with hooks or otherprotrusions on both sides, or may have its back surface formed by aurethane-based resin (as in a co-extrusion process) or coated with aurethane or tie layer of suitable material. Co-extrusion methods aretaught in U.S. Pat. No. 6,540,863, also incorporated herein byreference. Methods of securing the membrane directly to the foam arediscussed in more detail below.

In the construction shown in FIG. 5, the membrane 24 is adhesivelylaminated to a reinforcing material 30 (such as glass reinforced feltmaterial or Kraft paper, for example) that is either directly oradhesively bonded to the foam. Aluminum foil may also be employed, as avapor barrier. The other side of the foam board of FIG. 5 is shown witha standard paper skin 32.

Referring back to FIG. 4, the side of insulation board 22 opposite thereinforcing membrane 24 may also be provided with touch fasteners, forsecuring the board to the roof deck. These board-deck touch fasteners 33may be of a different shape, density and material than those of membrane24, and may be arranged to either cover the entire (or substantiallyentire) surface to provide additional reinforcement, or arranged inspaced-apart strips 34 as shown. Such strips may be provided only wherethe board will engage upper lands of a corrugated roof deck, forexample. In this example, the hook strips 34 are shown extending acrossthe width of the board, each having a width of about three inches (75mm). Securing the insulation boards to the roof deck with touchfasteners eliminates holes, fastener corrosion and pull out failuremodes. This may also enable lighter roof deck steel gauges, withreinforcements necessary only at bar joists, by distributing fastenerloads more uniformly across the decking and eliminating screw pull outconcerns.

Alternatively or additionally, in some installations, hot asphalt oradhesives such as urethane can be used to secure the foam boards to theroof deck structure.

In some implementations, a combination of touch fasteners and adhesivecan be used to secure the roofing membrane to the foam boards. Forexample, in any of the touch fastener configurations disclosed herein,an adhesive can be applied between the touch fastener materials inparticular areas, such as at roofing corners and edges, to furthersecure the fastening against separation.

In other cases, adhesive can substitute for touch fasteners in someregions. For example, adhesive can be used to adhere loop materialpresent on the back of the roofing membrane to conventional foam boardsalong a roof edge portion, while engagement of the loop material of theroofing membrane with hook fastener material across foam boards in acentral roof region. Thus, the loop fastener material present on theback of the roofing membrane can provide a suitable surface andstructure for touch fastener engagement and/or adhesion.

Loop touch fastener materials, such as a non-woven loop material, can belaminated to the roofing membrane to serve as a tie layer for attachmentcement. Suitable loop materials are found on “Fleece-back” materialsavailable from Carlisle SynTec Incorporated and Sika-Sarnafil Inc. Theseloop materials can be needled felts that use PET staple fibers ofapproximately 3 in. (76 mm) long by 3 to 6 denier, typically with crimp.Such materials can be produced in 2-6 oz. per square yard (70-200 gsm)weights. In a particular application, the loop touch fastener materialis a Velcro USA Inc. loop product characterize by 3 inch (75 mm) crimpedstaple fibers of 3.5 denier PET of about 3.3±0.5 oz. per square yard(110±15 gsm). The loop material can be stabilized and rolled onto andadhered to the roofing membrane. In other implementations, a similarloop material and application process can be used to provide the loopfastener material on the foam board.

In other implementations, the loop touch fastener material can includeknit constructions such as warp knit constructions. Examples of suchmaterials include yarns of Nylon 40 denier with about 9 to 13 filamentsand 3-7 grams per denier tenacity for the pile and ground. A suitablebinder coating for use with the knit construction is Sancure 1004-4B at2.6 oz. per square yard (88 gsm).

In some implementations, the hook and loop touch fastener materialsorientations are selected such that the hook material is present on theback of the roofing membrane and the loop material or a self-engaginghook material is present on the foam board facing.

In a particular implementation, a tie layer of Velcro brand FNL-300nonwoven loop can be fed into an insitu lamination process duringformation of the hooks, similar to the process used to produce theVelcro brand Onewrap® product. The resulting dual hook-loop backedproduct can then be laminated to the roofing membrane by insitu or gluelamination of the loop side of the material to the roofing membrane. Forexample, a PVC membrane can be cast over the loop fastener side toproduce a roofing membrane bearing a hook touch fastener material. Acomplementary loop fastener material is laminated to the foam insulationboard or other suitable underlayment. One suitable loop material is anylon warp knit loop material.

In another particular implementation, hook fastener elements and/or ahook base are calendared or extruded directly onto the roofing membrane.A preformed roofing membrane is passed through a nip between the moldrollers and a hook resin is applied to the membrane at the nip. Theapplied resin is forced into hook shaped cavities on a mold roll and theroofing membrane with the formed hooks is stripped from the mold roll.Sections of roofing membrane can be glued or welded together to producelarger membrane panels.

Wider hook panels can also be formed by laterally stretching molded orextruded hook tape, such as is discussed in U.S. Pat. No. 6,035,498, theentire contents of which are incorporated herein by reference. Arelatively thick layer of resin with integrally formed hooks can beformed on, or adhered to, a relatively thick sheet of roofing membraneand the two laterally stretched together to form a hook-bearing membraneof greater width.

Referring next to FIG. 7, membrane 16 is a continuous sheet of EPDM ofuniform thickness ‘t’ having a standard width ‘W’ of, for example, 2meters, 3 meters, 8 feet (2.4 m) or 10 feet (3 m) and continuous (roll)length. PVC is another suitable membrane material. The underside ofmembrane 16 features a loop material 36 that extends across all but aweld region 38 about three inches (75 mm) wide along one edge of themembrane. The loop material is Velcro USA loop 3905, a nylon knitmaterial with a fairly closed ground. Other useful loop materialsinclude non-woven materials, such as those disclosed inUS2004/0157036A1. The back side of the loop material may be coated witha urethane, for example, to bond to a PVC membrane. Other usefulloop-backed membranes include FLEECEBACK™, available from CarlisleSynTec Incorporated of Carlisle, Pa. and typically installed byexpanding a urethane adhesive between the insulation board and themembrane.

As shown in FIG. 8A, in a roofing application adjacent lengths ofmembrane 16 are overlapped, with the weld region 38 of the upper lengthextending over the adjacent length, such that the membrane substratematerial (e.g., PVC) surfaces are in direct face-to-face contact forheat or solvent welding or adhesion. Alternatively, as shown in FIG. 8B,the loop material 36 may extend over the entire width of each length ofmembrane, with adjacent lengths of membrane 16 butt-spliced at a jointcovered by a bare strip 40 of membrane material.

In some applications, membrane 16 is installed on roof surfaces ofdifferent heights, with membrane 16 extending, up vertical or inclinedsurfaces between the different roof sections. For example, membrane 16can extend up a wall or over a vertical divider between different roofsections. Thus, membrane 16 can be installed on horizontal, arched,inclined and even vertical or other contoured surfaces.

Portions of membrane 16 can be configured with graphics to provideaerially viewed advertising, for example, on single story buildingsamong office towers or along lower flight paths near airports. Theseportions can be configured to be removable and exchangeable to updatethe graphics appearing on the roofing installation.

Referring next to FIG. 9A, another roofing construction features apitched wooden roof deck 12, such as of plywood, to which theabove-described reinforced insulation board 14 is secured, either byadhesive or by touch fasteners (e.g., by providing the underside ofboard 14 with hooking fasteners as discussed above, and adhering alightweight loop material to the upper surface of the roof deck).Shingles 42 are then individually secured over the insulation in atypical overlapping pattern, beginning from a lower edge of the roofdeck. As shown in FIG. 9B, each shingle 42 has loop material 36 acrossits underside, and a patch of male fastener elements 26 on a portion ofits upper surface to be overlapped by a later-placed run of shingles.Preferably, the shingle is constructed to be particularly flexible, toenable loads to be distributed throughout the touch fastener interfacesunder load conditions.

Referring next to FIGS. 10 and 12, an apparatus 44 for producing facedfoam boards 46 includes an articulated, segmented chain 48 of U-shapedlower channel segments 50 driven about two rollers 52 a and 52 b. Chain48 is configured such that end surfaces of adjacent segments 50 meet andare held together during the straight run of chain 48 that passesthrough heater 54, in which chain 48 forms a moving U-shaped channel. Anupper chain 56 of flat plate segments 58 is driven about two rollers 60a and 60 b and also moves through heater 54 with end surfaces of platesegments 58 held together to form a moving continuous plate. As thesegments of the two moving chains are brought together prior to enteringheater 54, plate segments 58 of the upper chain nest within channelsegments 50 of the lower chain, such that the moving segmented chainsdefine a moving channel within heater 54, as shown in FIG. 12. The sideedges of plate segments 58 may seal against the inner surfaces ofchannel segments 50, or may have a small running clearance. Withinheater 54 the moving chain segments are restrained against verticalseparation by inside surfaces of the heater housing.

Still referring to FIG. 10, a continuous sheet of facing material 62(such as the paper skin 32 of FIG. 5) is introduced from roll 64 to themoving channel, disposed against and substantially covering the lowerinner surface of channel segments 50. Onto this facing material a liquidfoaming resin is sprayed by nozzle 66, distributed across the width ofthe facing material. The foaming resin 70 may be applied with multipleindividual nozzle heads, as shown in FIG. 11. Above the sprayed foamingresin, reinforcing membrane 24 is introduced to the forming channel as acontinuous length from roll 68, to become a reinforcing facing on theresulting product. A method of continuously producing an insulationboard is disclosed in U.S. Pat. No. 4,572,865, which is incorporatedherein in its entirety by reference.

As supplied to the channel, membrane 24 may already be laminated, eitheradhesively or directly, to a reinforcing or barrier material, such as apaper, fabric, film or foil backing. Membrane 24 is provided with moldedmale touch fastener elements (not shown in these views) extending fromits upper surface, away from the foaming resin. Alternatively, areinforcing facing of woven or knit or otherwise formed touch fastenermaterial may be used. In reinforcing backings with layers havingdiscrete fibers, such fibers may be selectively oriented to extend indirections corresponding to forces induced by roof loading, particularlywith respect to fastening bolt locations.

FIG. 13 shows that the lower facing material may also be in the form ofa sheet-form touch fastener material, such as another hook-bearing resinmembrane 24, onto which the foaming resin 70 is sprayed. FIG. 13 alsoshows resin 70 being applied by a single nozzle head 66 a that applies afan-shaped single spray pattern of resin that extends essentially acrossthe width of the channel.

In other cases, hook-bearing resin membrane 24 and foaming resin 70 arecoextruded to form a laminate. In other cases, the hook bearing resinmembrane 24 is extruded onto the foam board panel as described in U.S.Pat. Pub. No. US 2007-0264482 A1, which is incorporated herein in itsentirety by reference.

In one configuration, the resulting foam panel is reversible in that ahook-bearing resin membrane 24 is present on both sides of the panel.Alternatively, loop material may be provided on one side of the panel.Accordingly, the foam panels may be secured to the corrugated roofstructure using complimentary fastener elements adhered to or formed onthe corrugated roof structure.

Referring back to FIG. 12, as the materials progress through heater 54,foaming resin 70 expands to essentially fill the channel, pressingreinforcing membrane 24 up against segments 54 and bonding to the facingmaterials. The inner surfaces of the moving channel segments may betreated or coated so as to inhibit foam adhesion to the channels. As theresin foams and expands in thickness, vertical knit lines 72 can formbetween adjacent flows of resin. These knit lines can extend through thethickness of the foam and form regions of reduced board strength.Membrane 24 extends across these knit lines and reinforces the boardagainst rupture and splitting.

Referring back to FIG. 10, the foamed resin and bonded facing materialsexit heater 54 as a continuous, rigid laminate structure that can besevered into discrete boards 46, such as by a blade 73.

In some cases, the molding channel is a substantially closed tube aspreviously described. In other cases, the molding channel is asubstantially open corridor such as a single conveyor belt. Still inother cases, the molding channel is an open faced trench, for example,formed by just the lower portion of the channel illustrated in FIG. 12.Accordingly, the foam can be molded using a free rise process on asingle conveyor or open faced trench, or using a restrained rise processas illustrated in FIG. 12.

It can be particularly advantageous to inhibit gas bubble nucleation orgrowth at the interlace between the foaming resin and the facingmaterials during foaming, as extensive surface bubble growth can weakenthe bond between the foam and facing materials. One approach to reducingbubble growth on the back side of the facing materials, such as membrane24, is to make the foam-side of the facing smooth. In this way, foam isless prevented from lateral displacement across the face of the foam asbubbles form, and less likely for incompletely foamed resin to bestagnated. For facing materials having molded resin base membranes, themembrane base may be provided with a smooth back surface as molded.Alternatively, such smoothness may be provided by coating a facingmaterial having a non-smooth (e.g., knit or woven fabric) base with alayer of resin or by laminating such a base to a smooth film. Coatingsmay be employed that enhance bonding strength to the foamed resin.Another approach to reducing bubble growth is to provide the backsurface of the facing material with surface features, such as smallexposed fibers, that inhibit contiguous bubble growth beyond a certainsize. Yet another approach is to provide the base of the facing materialwith small holes or perforations, such as hole 74 shown in FIG. 6, or aporosity, that vents forming gases through the facing material withoutallowing the foaming resin to pass completely through the facingmaterials in quantities that would foul the exposed fastening elements.

When employing a reinforcing membrane 24 formed as a continuous sheet ofresin, significant shrinkage of the resin, such as can occur in heater54, in shipping or as installed, can result in undesirable boardwarpage. In such instances, the opposite side of the board can beprovided with a reinforcing membrane of similar shrinkage properties,such as a membrane of identical material and thickness. Shrinkage mayalso be reduced by annealing of the membrane resin prior to lamination.One apparatus and method for controlled annealing of a continuous hookmembrane is shown in FIG. 14. The formed hook membrane 24 is trainedabout a series of rollers 76 adjacent a radiant heater 78. The rollersinclude dancers that apply a controlled tension to the hook tape as itundergoes a series of bending reversals while being heated, effectivelyannealing the base of the hook membrane. The touch fastener elements,not shown in this figure, are disposed on the side of the membranefacing away from heater 78, such that radiant heat is applied to theback, non-fastening surface of the membrane. To promote annealing, themembrane may be vibrated during the annealing process, such as byvibrating one or more of the rollers or applying a fluttering air flowto the membrane. The applied tension may even be selected to besufficient, in some cases, to yield the resin of the membrane base.

Other means for controlling board warpage include providingwarp-resisting structural elements, either within the foam layer, withinthe reinforcing facing, or between the foam and facing. For example, arigid wire grid may be employed as an additional reinforcement, eitherwithin the foam (as rebar within concrete) or in or adjacent thereinforcing facing material.

Other foaming resins, such as polystyrene, may be employed that generatelower amounts of heat during foaming and thus may result in lesswarpage. Such resins can be extruded, injected or poured into a moldingspace.

With reference to FIGS. 15A-15C, washers 20, 20 a are configured toprevent pull-through or tear-out of fasteners 18 (see FIGS. 1 and 3)during uplift of membrane 16 during high winds. Accordingly, washers 20,20 a are configured in part as a function of the thickness and strengthof the foam layer and the anticipated uplift forces. Washers 20 are saidto have ‘anti-peel’ flaps in that the fastener element base isunrestrained near the edge of the washer to form a flap that can flex inresponse to a peel load, so as to place the fastener elements carried onthe flap in a shear-resisting orientation.

Washers 20 and 20 a are configured as rigid annular screw plates coveredwith male fastener elements 26 a similar to those carried by reinforcingmembrane 24. While male fastener elements 26 a of washers 20 need not bethe same as male fasteners 26 of membrane 24, continuity of malefastener elements 26 and 26 a across membrane 24 and washer 20, 20 a isbelieved to provide more uniform stress distribution. Relatively smallstress points adjacent washers 20 where peel may be initiated duringuplift may be reduced by inclusion of male fastener elements across thetop face of washer 20, 20 a. Such stress reduction may be particularlyuseful near the perimeter and corner sections of membrane roofinginstallations.

For example, washers 20 with fasteners 18 can be arranged in a densepattern near corners and edges and in a less dense pattern in thecentral field area of the roof. Similarly, washers 20 may be limited touse at the edges or corners where peel forces are strongest. In someapplications, fasteners elements 26 a on washer 20 a may be sufficientto secure a portion of membrane 16, without the need for fastenerelements 26 in an adjacent region of the underlayment 14. This wouldessentially transfer any uplift forces in the field through fastener 18to the underpinning roof structure, rather than to the foam boards.

It has been determined that male fastener elements 26 a can be providedon a two-three inch (5.1-7.6 cm) washer 20. Male fastener elements 26 amay be uniformly aligned across washer 20 such that the hook portions ofelements 26 a all face the same direction. Alternatively, male fastenerelements 26, 26 a may be circumferentially aligned such that the hookportions are radially arranged to provide increased shear resistance.

It has been determined that fastener elements 26 a can be provided on athree inch (7.62 cm) washer 20 a using a 0.25-0.50 inch (0.64-1.27 cm)flap 25 about the peripheral portion of washer 20 a.

Still in other implementations, it is advantageous for hook elements 26a to be uniformly oriented radially inward over the washer interiorportion to resist separation nucleation at the center of washer 20 a. Itcan be further advantageous to have the hook elements 26 a uniformlyoriented radially outward to better resist shear separation. Thus,fastener elements 26 a may be uniformly oriented outwardly, inwardly ormay be varied in oriented for a given application.

With reference to FIG. 15B and the cross-sectional view of FIG. 15Ctaken along line 15C-15C in FIG. 15B, one implementation of washer 20 aincludes an anti-peel perimeter flap 25. Flap 25 is formed from a freeperipheral section of the polymer base 23 that is common to malefastener elements 26 a. Flap 25 is effectively hinged about an innerperimeter where a central portion of base 23 is attached to washer 20 a.Membrane 24 experiences tensile forces during uplift or expansion andflap 25 flexes upward to provide an anti-peel or shear transition regionas the flap flexes to better align with the tensile forces in membrane24. Thus, flap 25 provides washers 20 a with increased peel resistanceduring uplift loading on membrane 24. Washers 20 a can be formed fromstamped metal or by injection molding of plastic. Fastener elements 26 amay be applied to washer 20 a before or after separation of washer 20 afrom a bulk precursor material or before or after installation of washer20 a on screw fasteners 18. In one example, fasteners 26 a are adheredor molded onto a precursor metal plate from which washers 20 a are to bestamped. A stamp die having a cavity or clearance to accommodatefasteners 26 a on the precursor metal plate is then employed to stampwashers 20 a from the metal plate. Washers 20 a may be stamped in theform of an annulus, oval, rectangle, polygon or other suitable shapebefore or after application of fasteners 26 a to washer 20 a.Continuously curved shapes such as circles or ovals are preferred insome applications to minimize stress concentrations. Washer 20 a may beflat, concave or convex before or after installation for a givenapplication. Addition of fine wires or creation of metal burrs orstamped projections on washer 20 a can provide loop engaging structureson washers 20 a.

In insert injection molded washer implementations having flap 25, a maskinsert or release agent is first applied to the washer in the peripheralsection of the washer, to prevent fastener resin from bonding withwasher material in the peripheral section. The release agent may be aoverprint varnish, for example, as described in U.S. Pat. No. 7,056,462.The release agent may be selected to cause only modest adhesion betweenwasher and fastener resin, such that flap 25 is initially secured to thewasher face until subjected to a peeling load that is less than the peelstrength of the fastener elements but sufficient to delaminate the flapfrom the washer face.

For example, for a three inch (7.62 cm) washer 20 a, the pressuresensitive adhesive is applied to the peripheral 0.25-0.50 inch(0.64-1.27 cm) portion of washer 20 a. The pressure sensitive adhesiveis sufficiently strong to retain flap 25 against washer 20 a in theabsence of a peel force. The pressure sensitive adhesive reattaches flap25 to washer 20 a upon removal of the peel force and return of flap 25adjacent washer 20 a. Releasable attachment of flap 25 provides for easyof storage, shipping and installation of washer 20 a and preserves flaps25 against deformation. Reattachment of flaps 25 by the pressuresensitive adhesive prevents build up of dirt or moisture under flaps 25.

With reference to FIGS. 16A-16B, one implementation of an anti-peelfeature includes a flap 25 a, 25 b that is initially adhered, laminatedor otherwise bonded to a rigid substrate 21, and is subsequentlyseparated or released from rigid substrate 21 when subjected to apredetermined peel force. Substrate 21 may be a washer, such as washer20, 20 a, a metal or plastic plate or other rigid or semi-rigidsubstrate. In one implementation, a pressure sensitive adhesive is usedto bond flap 25 a, 25 b to rigid substrate 21. The pressure sensitiveadhesive is applied to the area of rigid substrate 21 from which flap 25a, 25 b is to be released. A more permanent adhesive or bond is employedto bond the remainder of base 23 of fastener elements 26 a to rigidsubstrate 21.

A second anti-peel flap 25 b on rigid substrate 21 is configured torelease on the interior rather than periphery of rigid substrate 21. Forexample, a release agent is provided on rigid substrate 21 below flap 25b and base 23 of fastener elements 26 a is perforated or die cut alongan interior portion of substrate 21. Thus, any number of flaps 25 a, 25b may be used on substrate 21 to provide anti-peel resistance inmultiple directions or across any desired portion of substrate 21.

In another implementation shown in FIG. 16C, flap 25 c is stretchableand is unbonded or releasable from rigid substrate 21 about a centralflap area 27 to provide anti-peel resistance in multiple directions.Flap 25 c may be configured with an elongated open ended, or closedended, e.g., circular, unbonded central area 27. An elongated unbondedarea provides bi-directional anti-peel resistance while a circularunbonded area provides omni-directional anti-peel resistance.

Flaps 25, 25 a, 25 b, 25 c need not be of uniform width, thickness orhook/loop density but may be varied for a given application. In someapplications, it may be advantageous to switch the respective hook andloop fastener element positioning on roofing membrane 16 and washer 20.The pressure sensitive adhesive or other bonding means may be providedon substrate 21 and/or flaps 25 a-c. Flaps 25 a-c are configured to bereleasable or unbonded relative to substrate 21 employing any number ofrelease agents, mold inserts, temporary adhesives, pressure sensitiveadhesives, substrate surface treatments, mechanical peeling or otherseparation or release mechanism.

With reference to FIG. 17, a washer plate 20 d includes flexibleperipheral portions 25 d carrying touch fastener elements 26 d. Washerplate 20 d and fastener 18 tie foam board 14 to the roof deck. Touchfastener elements 26 d are configured to engage cooperating touchfastener material 36 present on the underside of roof membrane 16. Insome cases, touch fastener elements 26 d are hooks insitu molded on aflap or other suitably flexible peripheral portion 25 d of washer plate20 d.

In some cases, fastener elements 26 d comprise reinforced plastic hooklaminate material fixed to, e.g., glued to, washer 20 d or othersuitable screw plate or broad faced distributive plate. Washers 20 dwith fastener elements 26 d are placed hook up on foam board insulationpanels 14. Washers 20 d can be used in higher number and densities inroof corners and lower densities in the roof field. A screw is insertedthru the center hole of washer 20 d and is driven thru the insulationpanel and into the roof deck.

A fleece backed membrane 16 is rolled out over foam board insulationpanels 14 and washers 20 d. The assembly is then rolled or broomed topromote engagement of fastener elements 26 d and fleece 36. The flexibleperipheral portions 25 d flex upward during up-lift loading to followthe curvature of the membrane as the portions of membrane betweenwashers 20 d lifts, thereby maintaining the engagement between membrane16 and fastener elements 26 d in a shear mode for improved loadresistance. Flexure of the peripheral washer portion 25 d allows thetouch fastener closure to flex and remain engaged during membranedistortion from up-lift loading. The touch fastening can generallyresist greater overall loads in sheer compared to what are known in thetouch fastener industry as peel or tension loading orientations.Moreover, the touch fastener closure between washer 20 d and membrane 16is anchored directly to the roof decking, providing superior strengtheven to touch fastener closures between foam board 14 and membrane 16.In some cases, washers 20 d can provide the sole touch fastener closureor attachment of membrane 16 to the roof.

With reference to FIG. 18, one application features a method ofinstalling a roofing structure including securing a foam boardunderlayment 114 to a roof deck 112 with fasteners 120. Underlayment 114includes rigid foam boards having a flexible resin reinforcing membrane124 bonded across an upper surface of underlayment 114 and carrying anarray of male fastener elements 126 having stems formed of the flexibleresin. A flexible roof membrane 116 is positioned to extend overunderlayment 114 and flexible roof membrane 116 is a water-impervioussheet with a field of fastener elements 136 exposed on an undersidethereof to engage with male fastener elements 126 of underlayment 114 tosecure roof membrane 116. A slip sheet 150 is provided betweenunderlayment 114 and flexible roof membrane 116 to temporarily preventengagement of respective fastener elements 126 and 136 of underlayment114 and roof membrane 116. The position of flexible roof membrane 116over underlayment 114 is then accurately adjusted, e.g., aligned withunderlayment 114. Slip sheet 150 is then moved or removed to allowengagement of fastener elements 136 of flexible roof membrane 116 withfastener elements 126 of underlayment 114.

Slip sheet 150 is preferably a thin, flexible web that will not engagewith either of fastener elements 126 or 136. In some cases, slip sheet150 is a narrow masking material used only for positioning the edge offlexible roof membrane 116 at the edges, corner or seams of aninstallation. In other cases, slip sheet 150 is a larger maskingmaterial inserted under the width of flexible roof membrane 116 as it isunrolled or moved into place or, alternatively, under entire rows offlexible roof membrane 116.

In one application, slip sheet 150 is pre-rolled with flexible roofmembrane 116 for storage and shipping and ease of installation. In somecases, slip sheet 150 extends beyond the outer wrap of flexible roofmembrane 116 on the roll to provide a protective covering wrap about therolled flexible roof membrane 116. This protective covering preventsabrasion of flexible roof membrane 116 during storage, transport andinstallation.

In some cases, a second slip sheet may be used adjacent first slip sheet150 to prevent fastener elements 126 and 136 from engaging beyond theregion of first slip sheet 150. Slip sheets may be sequentiallypositioned and removed from between flexible roof membrane 116 andunderlayment 114 to engage incremental regions of fasteners 126 and 136.

In other cases slip sheet 150 is incrementally advanced or slid betweenflexible roof membrane 116 and underlayment 114 to incrementally engagefastener elements 126 and 136. For example, slip sheet 150 may extendthe width of a roll to be unrolled and may be slid along as flexibleroof membrane 116 is unrolled, positioned and pressed into engagement.Flexible roof membrane 116 can be brushed, broomed or swept to initiallyengage fastener elements 126 and 136 and subsequently rolled to enhancefastener engagement.

In some applications, the roofing membrane 116 is rolled out over thefoam board underlayment 114 without using a slip sheet and is broomed topromote engagement of the touch fasteners 126 and 136 present on roofingmembrane 116 and foam board underlayment 114.

In some applications, an adhesive can be applied to portions of the foamboard and/or membrane, for example along a roof edge portion. Theadhered portions can be broomed or rolled to promote adhesion.

In other applications, engagement of fastener elements 126 and 136 ismechanically enhanced using, for example, brooming, rollers, orbitalmassagers, multi-directional stretching and the like. Such rolling maybe accompanied by vibrating, oscillating or other action to enhancefastener engagement. In one application, multiple rollers with multipleorientations are passed over the membrane to increase fastenerengagement. A marker such as a removable ink is used to indicate treatedareas. Flexible roof membrane 116 may be stretched during or afterengagement of fasteners 126 and 136 to further enhance engagement.Moisture travels laterally through the interstices between fastenerselements 126 or 136 to escape from beneath flexible roof membrane 116.Moisture movement is facilitated by gravity, capillary action,evaporation, air movement, temperature variation and/or otherenvironmental effects and/or transport mechanisms. For example, the roofdeck 112 may be sloped and/or underlayment 114 tapered to provide forwater runoff on both sides of membrane 116.

With reference to FIG. 19, vents 152 are provided through membrane 116and include breathable membranes or shanty caps, on lateral roofsurfaces or are otherwise environmentally shielded to allow moisture toescape from under membrane 16 while preventing intrusion of rain andother moisture. Vents 152, vent coverings, flashing, flanges, pipecollars, curbing, drains, and the like may be fastened using hook andlook fasteners and/or bonded or sealed to membrane 116 to preventintrusion of rain or other moisture. Breathable membranes can bepositioned along membrane 16, to provide venting, for example, in placeof shanty caps at vents 152. Suitable breathable membranes includeGORTEX™, TYVEC™ and TYPAR™.

Vents 152 are located to provide a degree of breathing or air flowthrough the interstices between fasteners 126, 136. In some cases, vents152 are positioned along the roof perimeter to permit escape of run-offfrom below membrane 116. This is particularly important in the event ofa puncture or leak in membrane 116. Vents 152 are also provided atelevated central roof locations to permit escape of moist air that mayotherwise accumulate and dampen or rot underlayment 114 or other roofingmaterials.

The gap between the roofing membrane 116 and roofing underlayment 114 ismade up of the interstices between hook and loop elements 126, 136provide a moisture transport path. Transport and removal of moisturefrom between membrane 116 and underlayment 114 improves the life andefficiency of the underlayment. Additional venting is provided in oneimplementation by perforated tubes disposed between the membrane andinsulation. The tubes can terminate at an air vent or at the roofperimeter to provide ambient venting. Alternatively, forced air ventingmay be provided by periodically pushing air through the tubes to drivemoisture through the interstices between the hook and loop elementstowards the air vents.

Vents 152 further provide a pressure equalizing mechanism by whichpressure differentials across the roofing structure are equalized toreduce the effects of uplift. Vents 152 can include breathablemembranes, openable flaps, shanty caps or similar pressure releasepassages to pass moisture and pressure from below while excluding rainand pooled water. Vents 152 can be secured to membrane 116 or tounderlayment 114.

With reference to FIG. 20, another vented roofing installation 300 isshown with pressure relief valves 302 extending through a foam boardunderlayment 314, roofing membrane 316 and roof deck 306. Such systemsare designed to neutralize the pressure differentials caused by wind andkeeps the roof membrane 316 tightly secured to a monolithic roof deck orother air barrier over steel or wood. Relief valve 302 is a one-wayrelief valve, e.g., an EPDM flap, provided within a pipe and isconfigured to move to relieve pressure from under the roof. One suitablerelief valves are available from Stevens Roofing Systems. Touchfasteners 326 and 336 form a touch fastener closure between and acrossfoam board 314 and roof membrane 316.

With reference to FIG. 21, a ballasted roofing installation 400 isshown, with a roof deck 406. Ballast 402 is a weight such as gravel orstone pavers or blocks distributed over the roofing membrane 416. Insome ballasted implementations, paver blocks 402 are provided primarilyalong roof edges and in corner regions. Paver blocks 402 can be attachedto the roofing membrane 416 using cooperating touch fastener materials420, 422 on paver blocks 402 and roofing membrane 416. In some cases,paver blocks 402 supplement the hook and loop attachment provided bycooperating touch fastener materials 426, 436 of roofing membrane 416and underlying foam boards 414. In other cases, paver blocks 402 providethe primary or even sole means of securing membrane 416. In some cases,a distributed gravel ballast is used in the central regions of theroofing installation.

In some cases, vegetative trays, solar panels, or other roof-topaccessories can serve as ballast 402. For example, In some applications,touch fastener materials can be used to secure metal roof panels, solarpanels, HVAC platforms, trays for vegetative roofing assemblies,lightning protection devices or other roof mounted items. Such items canotherwise compromise the membrane if left loose or if dislodged duringhigh winds.

With reference to FIG. 22, an inverted roofing installation 500 is shownwith foam insulation boards 514 and/or paver blocks 502 installed overroofing membrane 516. Inverted installations are advantageous, forexample, where food processing or existing asbestos or wiring createconcerns with conventional roofing installations and through fasteners.In general, roofing membrane 516 serves as a waterproofing mechanism andthe upper exposed surface of the foam board 514 or ballast 502 isexposed to the elements.

One example of a conventional inverted installation is the “ProtectedMembrane Roofing System” provided by Stevens Roofing Systems, andincludes ballast pavers formed from a latex modified concrete on thesurface of extruded polystyrene insulation foam board. These foam boardpavers can serve as a weather barrier, ballast and walkable surface.

In an inverted roofing implementation, the touch fastener material 536of the roofing membrane 516 faces upward and the cooperating touchfastener material 526 of the foam board 514 is directed downward toengage the touch fastener material 536 of roofing membrane 516.Additional hook and loop touch fastener materials can be used to secureballast pavers 502 on top of foam board 514 to prevent scouring ordisplacement of pavers 502 at the edge of the roof.

In conventional paver blocks installations, the blocks are oftenstrapped together or are connected with interlocking tongue and groovechannels. Use of touch fasteners allows the paver blocks 502 to besecured to the roof in a spaced arrangement, i.e., without the need forinterconnection with adjacent paver blocks 502. In some cases, paverblocks 502 are additionally or alternatively adhered directly to the topof the foam board.

With reference to FIG. 23, a layered or stacked roof installation 200includes a first foam board layer 204 secured to roof decking 206 viathrough fasteners 208. A second foam board layer 214 is stacked orlayered on top of foam board layer 204. Second foam board layer 214 canbe secured to first foam board layer 204 using cooperating touchfasteners 220 and 222 as previously described or using adhesive or otherfasteners. Because through fasteners 208 do not extend beyond first foamboard layer 204 and because the second foam board layer 214 is securedby other than through fasteners 208, thermal bridging across throughfasteners 208 is greatly reduced. First and second foam board layers 204and 214 can be offset to distance the joints in one layer from those ofanother layer. Any number of layers can be stacked and various layerscan be tapered or otherwise contoured to provide desired slope or otherfeatures.

In different cases, the layered foam boards 204 and 210 are connected bytouch fastener closures such as hook and loop closures or self-engaginghook closures. In other cases, a touch fastener material such as a touchfastener material with engageable loops on both sides is insertedbetween boards faced with hook material. Still in other cases, a doublehook-sided sheet can be inserted between boards face with a loopmaterial. Still in other cases, one face of a board can include a hooktouch fastener material and the adjacent face of the stacked board caninclude a loop touch fastener material, and vice versa. Various othervariations or implementations included adhered, partially adhered,mechanically attached, and/or ballasted installations. A roofingmembrane (not shown) is secured across the upper board layer 214 withtouch fasteners, as described above.

With reference to FIG. 24, roofing membrane installations of the typedescribed were tested using a modified uplift test designed toapproximate wind uplift failure modes in such installations. The uplifttests were performed using a four-inch (10 cm) diameter circle of loopfastener material (not shown) attached to a vinyl roofing membrane 216and a six-inch (15 cm) or larger diameter area of hook fastener elementmaterial 226 adhered to a rigid acrylic backing plate 214 (6×6×0.25 in)(15.24×15.24×0.635 cm). The hook fastener elements 226 and loop materialwere adhered to acrylic plate 214 and vinyl membrane 216 using transfertape (not shown).

Transfer tape strips were cut and placed in a freezer for live minutesand applied across the entire back surface of hook fastener elementmaterial 226 and the top of acrylic plate 214. Additional transfer tapestrips were cut and placed in a freezer for five minutes and appliedacross the entire back surface of roofing membrane 216 and the back ofthe loop material. Ten membrane circles were then die cut for testing(five for pre-engagement testing and five for light engagement testing).

Threaded PVC caps 220 with flat, smooth machined tops were then adheredto the center of the vinyl membrane 216 circles. A first set of sampleswas rolled with an 11 lb. (5 kg) roller. A second set of samples wasonly lightly engaged, without rolling, using a single finger to pressdown at several intervals around the perimeter and center of the circle.For rolled engagement samples, PVC cap 220 was adhered using PVC cementafter rolling of the samples. For light engagement samples, PVC cap 220was adhered using PVC cement prior to engagement with hook tape. Thesamples were acclimatized to the test lab for a period prior to testing.

Acrylic backing plate 214 was secured in a test fixture 222 and PVC caps220 were then threaded onto an MTS tensile tester 224 with a 1000 lb/454kg. load cell used to pull upward on the center of the vinyl membrane216 circle, i.e., perpendicular to backing plate 214. This placed thesamples is tension at the center and shear at the outside edges,simulating the effects of uplift forces.

While the test samples were pulled, measurements were recorded for themaximum force and standard deviation (in lbs and psi) until failure ofthe fastening. For rolled samples, the maximum recorded uplift forcesranged from 45 to 63 pounds (200-280 Newtons) of force recorded atapproximately 0.8 inch (20 mm) of extension.

In some implementations, the roof is constructed to withstand an averageper hook up-lift force of at least about 0.022 Newton/hook (0.005lbf/hook), at least about 0.067 Newton/hook (0.015 lbf/hook) andpreferably at least about 0.133 Newton/hook (0.030 lbf/hook). Forexample, for a fastener array with a hook density of 1700 hooks persquare inch (260 per square cm) and hook strength of about 0.0088-0.0100lbf (0.04-0.045 Newtons) per hook, the fastening can withstand avertical loading of approximately 15 lbf per square inch (100 KPa).Where not all hooks are always fully engaged in a given fastening, anaverage force per hook is determined through uplift testing of afastening of a known hook density and engaged surface area.

It is believed that a certain amount of lateral low load fasteningdisplacement or shear slack between the fastener elements of the roofmembrane and those of the underlayment afford the fastening a degree offatigue resistance to repeated wind loading, as well as greater maximumload resistance.

With reference to FIG. 25, to determine shear slack, as that phrase isused herein, hook material 326 is laminated to a rigid substrate, suchas, for example, foam board 314 and is engaged with loop material 318laminated to a second rigid substrate 316. Fastening sample sections areprepared with a one inch by one inch overlap (6.45 sq. cm). Substrate314 is then loaded in a first direction relative to substrate 316 at apull rate of about 24 inches (61 cm) per minute using a programmable MTStester until a shear load F of 0.025 pounds per square inch (1.7 KPa) isobtained.

Once the target shear load has been reached in a first direction and thedisplacement determined, the direction of movement is reversed todetermine the displacement in the other direction at the same load. TheMTS tester is programmed to change directions with minimal delay toreduce the effects of relaxation or slippage in the fastening closure.Shear slack is then calculated as the sum of the in-plane movement ofsubstrate 314 relative to substrate 316, in two opposing directions atthe target load. For symmetrical hook fastener elements, such asmushroom hooks, the tests can be set up for any two opposing directions.

As shown in FIG. 26, with fasteners of symmetric machine directionconfiguration, shear slack A is generally equal to double the range ofmovement in any single given direction. The solid line position of loop318 shows a first loop extension relative to hook 326 and the dashedline position of loop 318 shows a second loop extension relative to hook326. Measurement of the range of movement of between these extensions ofloop 318 at the predetermined load provides a measurement of shear slackA.

The representative plot of FIG. 27 illustrates displacement of a roofingfastening over a range of shear loading. The range of displacement intwo opposed directions at the target 0.025 pounds per square inch (1.7KPa) loading is the shear slack of the fastening. In someimplementations, the fastening exhibits about 0.060 inch±0.030 in.(1.524 mm±0.762 mm) of shear slack under a shear force of about 0.025pounds per square inch (0.17 KPa). While smaller populations of hook andloop pairs may be separated below 0.025 pounds per square inch, thedistributed population of engaged hook and loop pairs exhibits shearslack of about 0.060 in (1.524 mm) at about 0.25 pound per square inch(1.7 KPa) shear load. In other words, the average one-directionaldisplacement from rest is approximately 0.030 in (0.762 mm) at 0.025pounds per square inch (0.17 KPa) shear load. It is believed that shearslack in the range of 0.030 to 0.090 inch (0.762 to 2.286 mm), andpreferably between 0.050 and 0.070 inch (1.27 and 1.778 mm), allowsexcessive uplift loads to be effectively spread over a larger number offastener engagements, thus improving overall load resistance.

It is believed that this range of shear slack accommodates limiteddisplacement of the fastening due to uplift loading by engagingadditional hook and loop pairs while extending the population of alreadyengaged pairs over a distributed fastening area. Thus, during initiationof an uplift cycle, displacement in the shear slack range serves tostrengthen the fastening, increasing resistance of the roofing fasteningto the uplift forces. It is also believed that this shear slack resultsin a more durable fastening than that provided by adhesive roofingsolutions, especially because conventional roofing adhesives typicallyfail with more than nominal displacement, particularly after numerouscycles. Moreover, hook and loop fasteners allow fastenings to knit orheal in the event of a partial separation.

Shear slack can be adjusted by varying the hook and/or loopcharacteristics. For example, a loop material having two or more loopsizes will tend to provide a lower shear slack than a material with thesingle greater loop length, and longer loops generally provide moreshear slack than shorter loops. Shear slack may also be varied byvarying the hook head thickness or head or stem width or shape.

Some implementations provide advances in hail resistance over existingroofing installations. Hail resistance is a function of the integrity ofa roofing installation sample before and after an impact from aprojectile under test conditions. Specifically, the degree ofdeformation or other damage and membrane separation can be measuredafter such impacts. For example, simulated hail impacts on aconventional adhered installation using paper or foil faced foam boardsproduced a tear or crease in the facing sheet and localized separationof the adhesive bond between the membrane and the foam board. Suchlocalized separation can later become an initiation zone for upliftduring high wind loads.

Through experimentation, it was determined that the loft and/or shearslack in a hook and loop touch fastener closure increases the separationresistance and puncture resistance of the roofing assembly. The hook andloop closure between the roofing membrane and foam board maintained itsintegrity after simulated hail impacts, preventing such impact zonesfrom becoming separation initiation zones during uplift loading. Thus,even though the foam board yielded locally from hail impact in sometests, the roofing membrane remained fully engaged with the foam boardacross the impact zone.

Hail impact simulations were performed using a 2.2 lb (1 kg), 2.5 in(63.5 mm) diameter smooth round weight dropped from a height of about 9feet (2.7 meters). Pressure sensitive film available under the PRESSURE™brand was placed between the foam board and roofing membrane to indicatethe pressure distribution characteristics of different materialscombinations. The density of the pressure film color patterns afterimpact was correlated with the degree and distribution of pressuresexerted.

Testing showed that a polymeric touch fastener facing material on thefoam board plastically deformed evenly around the impact zone, withoutany visible tearing or creasing. This even pressure distribution wasreadily visible from the surface of the test sample and furtherevidenced by consistent fine radial lines in the pressure film aroundthe impact zone. It is believed that plastic deformation of the touchfastener material facing on the foam board as well as relative movementbetween the complementary touch fastener materials of the roofingmembrane and foam board served to partially dissipate the hail impactloads. More significantly, it is believed that the presence of polymerichook fastener material across the broad face of the foam board helpspreserve the integrity of membrane to foam board attachment at any pointacross the roofing membrane.

A number of embodiments of the invention have been described.Nevertheless, it will be understood that various modifications may bemade without departing from the spirit and scope of the invention.Accordingly, other embodiments are within the scope of the followingclaims.

What is claimed is:
 1. A construction underlayment comprising a rigidfoam board having two broadest sides defining a thickness therebetween;and a reinforcing facing comprising a flexible resin membrane bondedacross one of the broadest board sides and an array of touch fastenerelements extending from the membrane and exposed for engagement, thetouch fastener elements having individual resin stems extendingintegrally from a surface of the membrane and molded heads definingoverhangs for engaging fibrous loops; and a fibrous tie layer betweenthe membrane and the foam board; wherein the tie layer includes areinforcing scrim, wherein the scrim has fibers at least partiallyembedded in resin of the membrane and formed of a material selected toinhibit chemical bonding between the scrim fibers and the membraneresin.
 2. The construction underlayment of claim 1, wherein the facingextends across an entire lateral extent of the board.
 3. Theconstruction underlayment of claim 2, wherein the array of touchfastener elements covers substantially all of one of the broadest boardsides.
 4. The construction underlayment of claim 1, wherein the foamboard defines foam knit lines extending along a length of the boardbetween adjacent foam portions, and wherein the tie layer includesfibers disposed across the knit lines.
 5. The construction underlaymentof claim 1, wherein the tie layer is adhered to the foam board.
 6. Aroof comprising: a roof deck; underlayment secured to the roof deck, theunderlayment comprising a rigid foam board having two broadest sidesdefining a thickness therebetween; and a reinforcing facing comprising aflexible resin membrane bonded across one of the broadest board sidesand an array of touch fastener elements extending from the base membraneand exposed for engagement, the touch fastener elements havingindividual resin stems extending integrally from a surface of themembrane and molded heads defining overhangs for engaging fibrous loops;and a fibrous tie layer between the membrane and the foam board; whereinthe tie layer has fibers partially embedded in resin of the membrane;and a flexible roof membrane extending over the underlayment, the roofmembrane comprising a water-impervious sheet with a field of fastenerelements exposed on an underside thereof and engaged with the fastenerelements of the underlayment to secure the roof membrane.
 7. The roof ofclaim 6, wherein the fastener elements of the underlayment and thefastener elements of the roof membrane form a fastening with a nominalshear slack of between about 0.762 mm (0.030 inch) and 1.524 mm (0.090inch).
 8. The roof of claim 6, configured to withstand an up-lift forceof at least about 4.309 Newton/square meter (90 pound/square foot). 9.The roof of claim 6, configured to withstand an up-lift force of atleast about 0.022 Newton/hook (0.005 lbf/hook).
 10. The roof of claim 6,wherein the underlayment is secured to the roof deck by engaged touchfasteners.
 11. The roof of claim 6, wherein the underlayment is securedto the roof deck in part by washers having touch fastener elements forengaging touch fastener elements on the roof membrane.
 12. The roof ofclaim 11, wherein the washer includes a peripheral anti-peel flap havingfastener elements for engaging fastener elements on the roof membrane.13. The roof of claim 6, further comprising ballast secured to an uppersurface of the membrane by touch fastener elements.
 14. The roof ofclaim 6, further comprising multiple layers of underlayment, wherein alower layer is secured to the roof deck via through fasteners and anupper layer is secured via one of touch fastener elements and adhesive.15. A method of roofing a structure, the method comprising: securingunderlayment to a roof deck, the underlayment comprising a rigid foamboard having two broadest sides defining a thickness therebetween; and areinforcing facing comprising a flexible resin membrane bonded acrossone of the broadest board sides and an array of touch fastener elementsextending from the base membrane and exposed for engagement, the touchfastener elements having individual resin stems extending integrallyfrom a surface of the membrane and molded heads defining overhangs forengaging fibrous loops; and a fibrous tie layer between the membrane andthe foam board; wherein the tie layer has fibers partially embedded inresin of the membrane; positioning a flexible roof membrane to extendacross the underlayment, the roof membrane comprising a water-impervioussheet with a field of fastener elements exposed across one face thereofto engage with the fastener elements of the underlayment to secure theroof membrane; and mechanically enhancing engagement of the fastenerelements of the flexible roof membrane and underlayment.
 16. The methodof claim 15, further comprising: providing a slip sheet between theunderlayment and the flexible roof membrane to prevent engagement of therespective fastener elements of the underlayment and roof membrane;adjusting the positioning of the flexible roof membrane over theunderlayment; and moving the slip sheet to allow engagement of thefastener elements of the flexible roof membrane and underlayment. 17.The method of claim 15, wherein mechanically enhancing the engagement ofthe fastener elements comprises rolling or brooming the outer surface ofthe positioned membrane.
 18. A construction underlayment comprising arigid foam board having two broadest sides defining a thicknesstherebetween; and a reinforcing facing comprising a flexible resinmembrane bonded across one of the broadest board sides and an array oftouch fastener elements extending from the base membrane and exposed forengagement, the touch fastener elements having individual resin stemsextending integrally from a surface of the membrane and molded headsdefining overhangs for engaging fibrous loops; and a fibrous tie layerbetween the membrane and the foam board; wherein the tie layer hasfibers partially embedded in resin of the membrane.
 19. A constructionunderlayment comprising a rigid foam board having two broadest sidesdefining a thickness therebetween; and a reinforcing facing comprising aflexible resin membrane bonded across one of the broadest board sidesand an array of touch fastener elements extending from the base membraneand exposed for engagement, the touch fastener elements havingindividual resin stems extending integrally from a surface of themembrane and molded heads defining overhangs for engaging fibrous loops;and a fibrous tie layer between the membrane and the foam board; whereinthe tie layer has fibers partially embedded in the rigid foam board.